New Delhi: China continues to sail a missile observation and tracking ship to Sri Lanka's port of Hambantota despite a request from Lankan authorities to defer the visit. India has expressed concern about the ship, which can be used to track ballistic missiles.

At 10 am today, the 23,000-ton Yuan Wang 5 is sailing West off the coast of Indonesia at a speed of 14 knots or 26 kilometres per hour.

It is expected to reach in Hambantota on Thursday at 9:30 am Indian time.

Yesterday, following requests from the Government of India ... the Sri Lankan Foreign Ministry reached out to the Chinese government and asked that the visit of the ship be deferred

"In the light of the need for further consultations, the Ministry has communicated to the Embassy of the People's Republic of China in Colombo to defer the visit of the said vessel to the Hambantota port,'' the Lankan foreign ministry said.

Beijing, without naming India, said it ''urges relevant parties to see China's scientific exploration in a reasonable and sensible way and stop disturbing normal exchanges and cooperation between China and Sri Lanka".

New Delhi has voiced its concern at the presence of the ship in the Indian Ocean, as it can be used to track satellites and inter-continental ballistic missiles.

The Yuanwang Class ship with a crew of 400, is equipped with several state-of-the art parabolic dishes and sensors, which India feels has serious security ramification.

By tracking Indian ballistic missile tests off the Odisha coast, China will be able to glean information on the performance of missiles and their exact range.

Government sources have said they are monitoring the progress of the ship.

India remains suspicious of China's growing influence in Sri Lanka, which owes large amounts of money to Beijing for infrastructure projects, including the $1.4-billion Hambantota Port.